ENH: Added GetUsedCommands() method.

Source/cmMakefile.h

@@ -326,6 +326,12 @@ public:
   const char* GetDefineFlags()
     {return m_DefineFlags.c_str();}
   
+  /**
+   * Get the vector of used command instances.
+   */
+  const std::vector<cmCommand*>& GetUsedCommands() const
+    {return m_UsedCommands;}
+  
   /**
    * Dump documentation to a file. If 0 is returned, the
    * operation failed.